{
    \usebackgroundtemplate{\includegraphics[width=\paperwidth]{background.png}} % 背景图片
    \usebeamercolor{structure}
    \begin{frame}[plain]
        \begin{center}
            \textcolor{fg}{\Huge \textbf{敬请各位老师批评指正！}}
            \vskip 1cm
            \textcolor{fg}{\large 焚膏油以继晷，恒兀兀以穷年。}
        \end{center}
    \end{frame}
}